Apparatus for perforating metal plates or the like



Sept; 3, 1940. w. .1. MAlR ET AL APPARATUS FOR PERFORATING METAL PLATESOR THE LIKE 2 Shee'ts-Sheet 1 Filed Dec. 28, 1938 F IGJ.

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ATTORNEY Sept. 3, 1940. w. J. MAlR ET AL 2,213,566 I APPARATUS FORPERFORATING METAL PLATES OR THE LIKE Filed Dec. 28, 1938 2 sheets-sheet2 mm Wk 27 I I INVENTORS m a? /izz ATTORNEY Patented Sept. 3, 1940.

UNITED sr ATEs APPARATUS FOR PERFORAT'ING METAL Y PLATES OR THE LIKEWilliam J. Mair, Binghamton. and Clarence C.

Butbeil, Endwell, N. Y minors to International Business MachinesCorporation, New York, N. Y, a corporation of New York ApplicationDecember as, 193s, Serial No. 248,086

- 9 Claims. (01. 164-88) This invention relates to punching apparatusfor punching metal plates or the like with a high .degree of accuracy.

In certainclasses of work it is necessary that 6 the perforations madein the metal plates be spaced very accurately and be clean-cut in orderto assure the proper functioning of the plates in their variousapplications. Such is the case, for example, in the making of dies forrecord 1 card punching machines such as described in the U. 8. Patent2,032,805 to C. D. Lake where close tolerances are essential.Accordingly, it is the general object of the present invention toprovide a punching apparatus having novel means for feeding the materialto be pierced a pred'etermined accurate distance between punchingoperations and locking the same against movement during said punchingoperations.

More specifically, it is the object of the present invention to providea novel screw type feed for the rack of a punching machine comprising arotatable shaft having 'a plurality of cams thereon cooperating insuccession with a plurality of notches in the rack in the course ofrotation of the shaft. so as to lock the rack during the punchingoperation and feed the same a predetermined accurate distance betweenpunching operations.

Further objects of the instant invention reside in any novel feature ofconstruction or operation or novel combination of parts present in theembodiment of the invention described and shown in the accompanyingdrawings whether within or without the scope of the appended claims andirrespective of other specific statements as to the scope of theinvention contained herein.

In the drawings;

Fig. 1 is a front elevation view of the machine showing the variousoperating parts.

Fig. 2 is a view of the stock showing the location of the holes to bepunched therein.

Fig. 3 is a plan view of. the die plates ofthe punching apparatus shownin Fig. 1 taken in the direction 3-3.

Fig. 4 is a sectional view of the machine taken at 4-4 of Fig. 1 in thedirection indicated by the arrows. I

Fig. 5 is a sectional view taken generally at 55 of Fig. 4.

Fig. 6 is a detail view of the punch mechanism shown in Fig. 5.

Fig. 7 is a sectional view taken in the direction 8- 8 is a sectionalview taken at 8-8 of Fig.

4 showing the shape of the feed cams and their spacing around theperiphery of the feed shaft.

It is apparent that the subject matter of the present invention may findapplications in ma- 5 chines other than punching machines. However, forpurposes of illustration and in order to forego too much detail, thedescription which follows is confined to .a preferred embodiment of theinvention as applied to a metalpunching machine. 10

Referring now to the drawings the frame structure as shown in Fig. 1'includes base It and upright members II. A crosshead I2 is supported byand is integral with a connecting member l3 to which a reciprocatingmotion is imparted by 15 any suitable means (not shown). The crossheadis guided in its movement by the members II, the down stroke being apunching stroke and the up stroke being a feeding stroke.

Assuming, for example, that a piece of stock go such as ll (Fig. 2) isto receive a plurality of perforations Ila in predetermined accuratelyspaced relationship with one another, the stock is placed on a rack I!and firmly positioned by locating pins l8 (Fig. 4). The rack is provided25 on one side with a plurality of notches which cooperate withaplurality of cams such as ll, l8, l9, and 20 to impart the necessarylongitudinal feed movement of the rack after each punching stroke. Thefeed cams are mounted so on a shaft 2| and have engaging portions orhigh points spaced equally around the periphery of the shaft 2|, as bestshown in Fig. 8. The high point of one of the cams is normally. inengagement with the rack Ill, locking the latg5 ter against movement ineither direction. Upon rotation of shaft 2| a predetermined amount, in amanner to be described later, the high point of the cam in engagementwith the rack is moved away and the high point of another cam is movedinto engagement with the following notch in the rack. Each of thehighpoints is provided with a beveled leading surface so that in movinginto engagement with the rack the beveled surface engages a wall of onenotch in 45 the rack and cams the latter forward a predetermineddistance. 1

At the beginning of operations, the first cam l1 ise'ngaged in the firstnotch in rack Ill as shown in Fig. 4. On the downstroke of cross- 50head l2, a lever 22 turns about the shaft 2i carrying a ratchet pawl 23downward to engage in a succeeding notch of ratchet wheel 24. Theratchet wheel is provided with four teeth equally spa ed around itsperiphery so that it requires v I9 into engagement withthe third notchof rack Feeding occurs on the up-stroke of the crosshead H, the lever 22being connected to the crosshead by a link 25, and during the upstrokethe pawl 23 advances the ratchet 24 ninety degrees in a clockwisedirection as viewed in Fig. 1'.

The advancement of ratchet 24 in the above manner causes the high pointof the second cam l8 to move into engagement with the second notch ofrack II and, as it does so, to feed the rack a predetermined distance aspreviously described. During the next downstroke, punching occurs in anew location on the stock 14 and the rack and stock are held firmlylocked against movement by the engagement of cam I8 with rack ll.

The following upstroke brings the third cam l5. moving' the rack and thestock ahead to present a new portion ofthe surface of the stock for apunching operation. Likewise, on thenext upstroke, the fourth cam 20engages in the fourth notch of rack l5 and again advances the rack andthe stock inthe same manner. Itwill be noted that when ratchet 24 isturned one more step that cam I1 is again moved into engagement withrack l 5, since one revolution will have been completed. This time,however, cam l1 engages in the second notch of the rack, Cor--respondingly, as the other cams are broughtinto engagement with therack, they will engage a notch one removed from the notch which theyengaged on the preceding revolution of shaft 2|.

By the abovefeeding method, the number of notches may be considerablyless than the number of holes to be punched in the stock. Suppose, forexample, that the number of holes to be cut in the stock is 80, then thenumber of notches in the rack need be only 22. It is understood thatmore sets of cams may be secured to shaft 2|, so that two or three camsare engaged with the rack simultaneously. This would assure a moreperfect alignment over a greater period of time due to less wear and agreater rigidity. A bracket 26 is fastened at one end of rack II bymeans of screws 21 and, upon the completion of the last punchingoperation, this bracket moves into the path of pawl 23 so as to preventit from further engagement with ratchet 24, thus discontinuing anyfurther advancement of the rack Ii.

As for the punching mechanism, a pimch 3|! (Fig. 5) is mounted in aholder comprising the two members 3! and 32 held in a clamping positionon punch 30 by means of screws 22, the punch and its holder beingstationary. A set of four die plates 28 are arranged as shown in Fig. 3and fastened to the bottom surface of the crosshead I 2 by screws 29.When the crosshead moves down, the die plates 22 bear upon the stock 14,and in turn upon the rack I5 and a stripper 34 moving all of them down.During this downward motion the punch 20 pierces the stock and entershole 2! formed by the die plate 28. The stripper 24 is guided by rigidpins 26 in its vertical motion and is returned to its normal position bymeans of coil springs 21.

Immediately following the punching of the last hole in the stock, therack may be returned to the starting point by rotating shaft 2| a slightamount to a point where any two of the engaging surfaces of the camswill straddle rather than engage the rack. Then, as will be best understood from Fig. 8, the rack may be moved freely back to the startingpoint. This presents a time saving advantage over an ordinary worm driveconstruction where the worm shaft corresponding to shaft 2| would haveto be rotated in the" reverse direction to feed the rack back to thestarting point.

The shaft 2|, although quite free to rotate under the pawl and ratchetdrive, is mounted in bearings 28 with very little end play so that itdoes not turn under vibration caused by the impact of the punchingelements during a punching operation. The structure is best shown'inFig. '7 which reveals threaded portions 2 la at each end of the shaftadapted to receive nuts 39. At the upper portiorrof the shaft as viewedin this figure, the cams II to 20' are mounted with spacers 40therebetween, both the cams and the spacers being keyed to the shaft.Nut 29 for the upper portion is held in position by a screw 4l providedfor this purpose. The pawl and ratchet assembly already described arealso keyed to shaft 2| and' secured in position by a nut 39 cooperatingwith threaded portion 21a at the lower end of the shaft as viewed inFig. 7.

While there has been shown and described and pointed out the fundamentalnovel features of the invention as applied to a single modification, itwill be understood that various omissions and substitutions and changesin the form and details of the device illustrated and in its operationmay be made by those skilled in the art without departing from thespirit of the invention. It is the intention therefore to be limitedonly as indicated by the scope of the following claims.

What is claimed is:

1. A machine to punch a series of holesin succession in work such as adie plate or the like, comprising a work support, a fixture having anopening therein and provided with guide means,

for mounting the work support for slidable moveon the support to movethe support positively step by step and to lock the support positivelyagainst movement in either the direction of the spacing of the holes orin the opposite direction between said steps of movement, and punchingmeans comprising a punch element and a die, the punch moving through theopening in the fixture to perforate the work in cooperation with the diein the course of a punching operation.

2. A machine for punching a series of successive holes in work such as adie plate or the like, comprising a work support adapted for movementalong a given plane in the direction of the spacing of the holes, drivemeans acting on the support to move the support positively step bystepand lock the support positively against movement in either directionalong said plane between said steps of movement, punching means forpunching a-hole in the work on the support between each said stepofmovement, the

work support being also mounted to move in drive means acting on thesupport to move said 1 support positively step bystep and to lock thesupport positively against movement in eitherthe other side of the workfor impacting said work, and holding it firmly against movement withrespect to the work support and then, while holdingit, forcingittogether with the work support against the punch to cause the latter toperforate the work. I

4. In a machine of the character described having punching elementsadapted to be moved relatively toward each other during a punchingoperation for punching a series of successive holes in work such as adie plate or the like, a movable rack supporting the work and having aplurality of spaced notches therein, a rotatable shaft having camsurfaces arranged to cooperate with the notches in the rack,intermittent means for rotating the shaft a predetermined amount at atime for bringing the cam surfaces successively into engagement withsaid rack to step the rack and the work forward a predetermined distancemits yielding movement of the rack along'the line of movement of thepunching elements during a punching operation.

5. In a machine of the character described having punching elementsadapted to be moved relatively toward each other during a punchingoperation for punching a series of successive holes in work such as adie plate or the like, a movable rack supporting the work and having aplurality of spaced notches therein, a rotatable shaft having aplurality of cams with engaging surfaces spaced equally around theperiphery of said shaft, arranged to cooperate with the notches in therack, intermittent means for rotating the shaft a predetermined amountat a time to bring the cams into engagement with the rack in succession,said rack together with the work being moved forward in a directiontransverse to that taken by the punching elements during a punchingoperation a predetermined distance upon each engagement in accordancewith the spacing of the holes, and means whereby a cam engaged with anotch in the rack upon interruption of the rotation of the shaft lockssaid rack against forward or backward movement in said direction butpermits yielding movement of the rack and the work along the line ofmovement of the punching elements during a punching operation.

6. In a machine of the character described including punching elementsand means providing relative movement between said elements during apunching operation for punching a series of successive holes in worksuch as a die plate or the like, a rotatable shaft, a plurality of camshaving engaging surfaces spaced equally around the periphery of saidshaft, said engaging. surfaces being provided with beveled leadingedges, pawl and ratchet means for rotating the shaft a predeterminedamount on each feed ,stroke of said pawl and ratchet means, and a feedrack supporting the work and having spaced notches therein cooperatingwith the said cams during the rotation of the shaft to feed the rackforward a predetermined distance in a direction transverse to the lineof movement of the punching elements during a punching operation uponengagement of the beveled edges of each of the cams with related notchesin the rack in accordance with the spacing of the holes, the engagingrotatable shaft having a plurality of cam surfaces, a feed rack forminga mounting for the material and adapted to cooperate with said camsurfaces to lock the rack against movement during the punchingoperation, and means automatically set up by the die during saidpunching operation and effective upon the return stroke to rotate theshaft and the cam surfaces a predetermined amount so as to feed the racktogether with the material a predetermined distance.

8. In a punching machine, a stationarypunching element and a movabledie, means for moving the die toward the punch element to effect apunching operation in a piece of material, a feed rack adapted to carrysaid material and having a plurality of spaced notches therein, arotatable shaft provided with cam surfaces thereon ar-' ranged tocooperate with the notches inthe rack, and means conditioned uponmovement of the die toward the punch element and effective upon thereturn stroke of the die to rotate'the shaft a predetermined amount, theaforesaid cam surfaces in the course of the rotation of the shaftcausing the rack and the material to be fed a predetermined distance.

9. In a punching machine of the character described,a die and a punchingelement, means to move the die relatively ,toward said element to effecta punching operation, a rotatable shaft having a plurality of camsurfaces, a feed rack provided with spaced notches therein, one of whichis adapted to engage with one of the notches in the rack to lock therack against movement during the punching operation, and means preparedfor operation during the punching movement of the die with respect tothe punching element and operated on the return movement to rotate theshaft a predetermined amount to move the engaged cam surface away

